Added page to Observatory to display native memory allocation information.

runtime/observatory/lib/src/models/repositories/sample_profile.dart

Index: runtime/observatory/lib/src/models/repositories/sample_profile.dart
diff --git a/runtime/observatory/lib/src/models/repositories/sample_profile.dart b/runtime/observatory/lib/src/models/repositories/sample_profile.dart
index 9f8e80ea7e18e18cba307a75f1f120f6d231f176..e28554eecd7f1826af301c4c68df6b9cc924d663 100644
--- a/runtime/observatory/lib/src/models/repositories/sample_profile.dart
+++ b/runtime/observatory/lib/src/models/repositories/sample_profile.dart
@@ -8,6 +8,8 @@ enum SampleProfileTag { userVM, userOnly, vmUser, vmOnly, none }
 
 enum SampleProfileLoadingStatus { disabled, fetching, loading, loaded }
 
+enum SampleProfileType { cpu, memory }
+
 bool isSampleProcessRunning(SampleProfileLoadingStatus status) {
   switch (status) {
     case SampleProfileLoadingStatus.fetching:
@@ -42,3 +44,9 @@ abstract class IsolateSampleProfileRepository {
       IsolateRef isolate, SampleProfileTag tag,
       {bool clear: false, bool forceFetch: false});
 }
+
+abstract class NativeMemorySampleProfileRepository {
+  Stream<SampleProfileLoadingProgressEvent> get(
+      VM vm, SampleProfileTag tag,
+      {bool clear: false, bool forceFetch: false});
+}